Submission #408957

#	Time	Username	Problem	Language	Result	Execution time	Memory
408957		MohamedAhmed04	Strange Device (APIO19_strange_device)	C++14	100 / 100	551 ms	25312 KiB

strange_device

#include <bits/stdc++.h>

using namespace std ;

const long long inf = 4e18 ;
const int MAX = 1e5 + 10 ;

bool Overflow_Mul(long double x , long double y)
{
	return (x * y > inf) ;
}

int arr[MAX] ;
int n ;
long long a , b ;

vector< pair<long long , long long> >vp ;

int main()
{
	ios_base::sync_with_stdio(0) ;
	cin.tie(0) ;
	cin>>n>>a>>b ;
	long long x = a / __gcd(a , b+1ll) ;
	if(Overflow_Mul(x , b))
		x = inf ;
	else
		x *= b ;
	long long st = -1 ;
	for(int i = 0 ; i < n ; ++i)
	{
		long long l , r ;
		cin>>l>>r ;
		if(r-l+1ll >= x)
			return cout<<x<<"\n" , 0 ;
		if((r % x) < (l % x))
			st = max(st , (r % x)) , vp.emplace_back((l % x) , x-1ll) ;
		else
			vp.emplace_back((l % x) , (r % x)) ;
	}
	sort(vp.begin() , vp.end()) ;
	long long ans = st+1ll , Max = st ;
	for(auto &p : vp)
	{
		Max = max(Max , p.first - 1ll) ;
		ans += max(0ll , p.second - Max) ;
		Max = max(Max , p.second) ;
	}
	return cout<<ans<<"\n" , 0 ;
}		

• Subtask 1: 10 / 10
• Subtask 2: 5 / 5
• Subtask 3: 5 / 5
• Subtask 4: 5 / 5
• Subtask 5: 5 / 5
• Subtask 6: 20 / 20
• Subtask 7: 20 / 20
• Subtask 8: 30 / 30